As far as I remember, BIS have made several videos, demonstrating what a mainstream player can really achieve using mission editor. In my opinion, that should be enough for a even slightly motivated user in creating something by himself, not being a typical user anymore, but a developer of "something", no matter it's small. It's always encouraging to start with little things and constantly proceed to bigger ones, in fact that's what scheme is used to finnish huge projects.
Interface improvements sounds good. I agree that it would be very appreciated by new customers. BIS could make modding tutorial videos integration into UI, too. Well, I understand that all of your statements are subjective opinion and everyone has its own.
Also, it might be possible to create a simple mod, which modifies UI drastically, to present mission making and modding tutorials real-time in menu. It can be text or video content, that does not matter, really.
P.S.: The main problem may become lack of altruistic community members, but we already have enough of them!